The present invention relates to an apparatus for sampling material moving through a pipe or chute in a generally vertically downward direction. More particularly, the invention relates to such a sampler capable of obtaining samples from a chute which may be pressurized without releasing significant portions of dust or fumes into the atmosphere.
Various previously known sampling devices are described in U.S. patents such as the following: U.S. Pat. No. 608,834 describes a sampling machine that discharges samples through the atmosphere into a receiver. U.S. Pat. No. 1,649,241 describes a sampler designed for unattended automatic operation while sampling milk or other liquid. U.S. Pat. No. 1,966,712 describes an automatic sampler for periodically being air driven into a collecting position and spring returned into a sample discharging position. U.S. Pat. No. 2,683,373 describes a grain sampling cup arranged to be reciprocated and rotated from a chute closing position to a sample collecting position along a vertical grain chute. U.S. Pat. No. 3,076,341 describes a sampling cup which is automatically rotated from a non-collecting to a collecting position as it is moved into a product chute. U.S. Pat. No. 3,381,537 describes an inclined tubular sampler arranged for continuously discharging particles, which are collected by selectively shaped openings, through the atmosphere into a sample receiving hopper.